Fading caused by perspiration is characterized by location on the garment, such as under the arms, across the shoulders, around the neck over the thighs, and around the waistline. Colors should be resistant to perspiration. Perspiration normally has a wide pH range of from 3.5 to 8.0. Fresh perspiration is normally acidic. Bacterial action over a period of time makes it alkaline. Excessive acidity or alkalinity is an individual condition against which there can be no assurance of colorfastness. Acceptable resistance is specified in ASTM Standard Performance Specifications for Textile Fabrics published by American Society for Testing and Materials. 7